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Radical reactions

18 real reactions from the literature: benzylic halogenation on alkylbenzenes and thiophenes; allylic halogenation on α,β-unsaturated esters, α,β-unsaturated acids and trans-1,2-disubstituted alkenes; and more. Each scheme shows starting materials, conditions and products, with the yield and reference where the source reports them.

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  1. Benzylic halogenation: 4-bromotoluene (an alkylbenzene) with NBS; AIBN gives 4-bromobenzyl bromide (the benzylic halide). 100% yield.
    Benzylic halogenationBioorg. Med. Chem. Lett. 2016, 26, 2526

  2. Allylic halogenation: crotonic acid (an α,β-unsaturated acid) with NBS, (PhCO2)2 gives 4-bromocrotonic acid (the allylic bromide). 93% yield.
    Allylic halogenationBioorg. Med. Chem. 2014, 22, 2366

  3. Radical cyclization: bromomethyl-dimethyl-(3-methylbut-2-enoxy)silane (a primary alkyl bromide) with AIBN; SnBu3H gives 2,2-dimethyl-4-propan-2-yloxasilolane (the cyclized product). 71% yield.
    Radical cyclizationJ. Org. Chem. 2016, 81, 8544

  4. Radical dehalogenation: 7,7-dibromodispiro[2.0.2.1(3)]heptane (a gem-dihalide) with Bu3SnH, AIBN; EtOH / 40 °C gives 7-bromodispiro[2.0.2.1]heptane (the dehalogenated product).
    Radical dehalogenationEur. J. Org. Chem. 2003, 4234

  5. Radical addition: a vinyl iodide with AIBN; SnBu3H gives (E)-6-hydroxytridec-4-enenitrile (the addition product). 81% yield.
    Radical additionTetrahedron Lett. 1994, 35, 9605

  6. Benzylic halogenation: 3-methylthiophene with NBS; benzoyl peroxide, benzene, Δ gives 3-(bromomethyl)thiophene (the benzylic halide).
    Benzylic halogenationOrg. Synth. Coll. Vol. 4, p. 921

  7. Allylic halogenation: (E)-hept-2-ene (a trans-1,2-disubstituted alkene) with NBS; (PhCO)2O, CCl4, Δ gives (2E)-4-bromo-2-heptene (the allylic bromide).
    Allylic halogenationOrg. Synth. Coll. Vol. 4, p. 108

  8. Radical cyclization: N-(2,2,2-trichloro-1-phenylethyl)prop-2-en-1-amine (a tertiary alkyl chloride) with SnBu3H; AIBN gives 3,3-dichloro-4-methyl-2-phenylpyrrolidine (the cyclized product). 79% yield.
    Radical cyclizationTetrahedron Lett. 1987, 28, 3953

  9. Radical dehalogenation: a secondary alkyl iodide with SnBu3H; AIBN gives the dehalogenated product. 87% yield.
    Radical dehalogenationAngew. Chem. Int. Ed. 2012, 51, 6176

  10. Benzylic halogenation: o-xylene (an alkylbenzene) with Br2, (4 equiv.); hν gives o-bis(bromomethyl)benzene (the benzylic halide).
    Benzylic halogenationOrg. Synth. Coll. Vol. 4, p. 807

  11. Allylic halogenation: an α,β-unsaturated ester with AIBN gives the allylic bromide. 85% yield.
    Allylic halogenationOrg. Lett. 2013, 15, 3054

  12. Radical cyclization: a vinyl bromide with SnBu3H; AIBN gives 1-methyl-3-propan-2-yl-2-prop-1-ynylcyclopentene (the cyclized product). 85% yield.
    Radical cyclizationJ. Org. Chem. 1990, 55, 2983

  13. Benzylic halogenation: p-xylene (an alkylbenzene) with Br2, hν; Δ gives 1,4-bis(bromomethyl)benzene (the benzylic halide).
    Benzylic halogenationOrg. Synth. Coll. Vol. 3, p. 788

  14. Benzylic halogenation: (3-bromopropyl)benzene (an alkylbenzene) with NBS, benzoyl peroxide; CCl4, Δ gives 1,3-dibromo-1-phenylpropane (the benzylic halide).
    Benzylic halogenationOrg. Synth. Coll. Vol. 5, p. 328

  15. Benzylic halogenation: 4-chlorotoluene (an alkylbenzene) with Cl2, PCl5; hν, Δ gives 1-chloro-4-(chloromethyl)benzene (the benzylic halide).
    Benzylic halogenationOrg. Synth. Coll. Vol. 2, p. 133

  16. Benzylic halogenation: 2-nitrotoluene (an alkylbenzene) with NBS; benzoyl peroxide, CCl4, Δ gives alpha-bromo-2-nitrotoluene (the benzylic halide).
    Benzylic halogenationOrg. Synth. Coll. Vol. 5, p. 825

  17. Benzylic halogenation: an alkylbenzene gives the benzylic halide. 63 % yield.
    Benzylic halogenationJ. Org. Chem. 2011, 76, 5335

  18. Allylic halogenation: 5,6-dihydro-2H-pyran-2-one (an α,β-unsaturated ester) with excess NBS, (PhCO2)2 gives the allylic bromide. yield not provided yield.
    Allylic halogenationCurr. Med. Chem. 2013, 20, 3797